What does it mean to be a boy? What does it mean to be a girl? Is there a difference between the two genders, other than physical differences?

To be a boy it means to have masculinity. To choose what seems like a good choice or something that looks masculine something that looks like a boy picks.
Like if you want to get a pet and you are a boy you would probably choose a dog because it is masculine ( my opinion). Also if you are a boy you would want to choose a sport that is rough like hockey or basketball and soccer. So basically what it means to be a boy is to do something masculine. But some boys don't do those things and do something that isn't masculine like painting or singing and some boys actually do most of the above like singing, playing sports and painting so boys are diverse in choosing what they want to do.

What it means to be a girl is to have femininity. Like to shop for feminine clothes like dresses or skirts and care about how they look. The most common thing that girls do is gossip it seems like they create more rumours and stories than boys. The way girls think is different because if a boy has a opinion a girl will disagree with it. Girls also care about nature and animals more than boys so that is feminine. To be a girl it means to have long hair (my opinion) but they can have it short or long either way. A girl can do what a boy does and a boy can do what a girl does because there are some people who do those things.

There is no difference between the two genders because as I have said a boy can do what a girl does and the other way around so the only difference is the physical appearance of the two genders.